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Related papers: Cosmic-Ray Convection-Diffusion Anisotropy

200 papers

Recent data from ATIC, CREAM and PAMELA revealed that the energy spectra of cosmic ray (CR) nuclei above 100 GeV/nucleon experience a remarkable hardening with increasing energy. This effect cannot be recovered by the conventional…

High Energy Astrophysical Phenomena · Physics 2015-06-11 N. Tomassetti

In our previous work, we have investigated Galactic cosmic ray (GCR) spectra and anisotropy from 100 GeV to PeV, under anisotropic propagation model with axisymmetric distributed galactic sources. Numerous observational evidence have…

High Energy Astrophysical Phenomena · Physics 2024-12-24 Aifeng Li , Zhaodong Lv , Wei Liu , Yiqing Guo , Fangheng Zhang

The growth of magneto-hydrodynamic fluctuations relevant to cosmic ray confinement in and near their sources, and the effects of local plasma conditions is revisited. We consider cases where cosmic rays penetrate a medium which may contain…

High Energy Astrophysical Phenomena · Physics 2021-02-10 B. Reville , G. Giacinti , R. Scott

We investigate the transport of spectrally resolved cosmic ray (CR) protons with kinetic energies between $1-100$ GeV within the dynamic, multiphase interstellar medium (ISM), using a two-moment CR fluid solver applied to a TIGRESS MHD…

High Energy Astrophysical Phenomena · Physics 2025-07-02 Lucia Armillotta , Eve C. Ostriker , Nora B. Linzer

We introduce a novel diffusion model for the propagation of cosmic rays (CRs) that incorporates an anisotropic diffusion tensor of a general form within a realistically modeled large-scale Galactic magnetic field. The parameters of the…

High Energy Astrophysical Phenomena · Physics 2025-07-22 V. D. Borisov , V. O. Yurovsky , I. A. Kudryashov

We discuss recently published results of two-dimensional measurements of the cosmic ray anisotropy in the energy range 1-100 TeV. It is demonstrated that, in spite of pretence of the authors to measure the anisotropy in more detail than it…

Astrophysics · Physics 2008-04-29 Yu. M. Andreyev , V. A. Kozyarivsky , A. S. Lidvansky

We explore the possibility that the recently detected dipole anisotropy in the arrival directions of~$>8$~EeV ultra-high energy cosmic-rays (UHECRs) arises due to the large-scale structure (LSS). We assume that the cosmic ray sources follow…

High Energy Astrophysical Phenomena · Physics 2017-12-06 Noemie Globus , Tsvi Piran

Using a hybrid kinetic magnetohydrodynamic formalism incorporating the effects of pressure anisotropy, we simulate the evolution of a turbulent collisionless plasma in six different models covering the sub/super-sonic and…

High Energy Astrophysical Phenomena · Physics 2013-12-31 M. S. Nakwacki , J. Peralta-Ramos

The spatial diffusion of energetic particles in a magnetic field composed of a large-scale background and a small-scale turbulent component should be expected to be anisotropic. While such anisotropic diffusion has been known for quite a…

High Energy Astrophysical Phenomena · Physics 2025-07-17 Julien Dörner , Jonas Hellrung , Julia Becker Tjus , Horst Fichtner

The origin of cosmic rays (CRs) and how they propagate remain unclear. Studying the propagation of CRs in magnetohydrodynamic (MHD) turbulence can help to comprehend many open issues related to CR origin and the role of turbulent magnetic…

High Energy Astrophysical Phenomena · Physics 2025-01-10 Na-Na Gao , Jian-Fu Zhang

As cosmic rays (CRs) propagate in the Galaxy, they can be affected by magnetic structures that temporarily trap them and cause their trajectories to display chaotic behavior, therefore modifying the simple diffusion scenario. When CRs…

High Energy Astrophysical Phenomena · Physics 2023-02-01 Vanessa López-Barquero , Paolo Desiati

Isotropic diffusion models for Galactic cosmic ray transport put tight constraints on the maximum convection velocity in the halo. For a half halo height of 4 kpc the maximum convection speed is limited to 40 km/s in the halo, since…

Astrophysics of Galaxies · Physics 2009-10-13 Iris Gebauer , Wim de Boer

The hard X-ray (>2 keV) emission of the local and distant Universe as observed with the HEAO1-A2 experiment is reconsidered in the context of large scale cosmic structure. Using all-sky X-ray samples of AGN and galaxy clusters we remove the…

Astrophysics · Physics 2009-10-31 C. A. Scharf , K. Jahoda , M. Treyer , O. Lahav , E. Boldt , T. Piran

We investigate stochastic particle acceleration in accretion flows. It is believed that the magnetorotational instability (MRI) generates turbulence inside accretion flows and that cosmic rays (CRs) are accelerated by the turbulence. We…

High Energy Astrophysical Phenomena · Physics 2016-05-25 Shigeo S. Kimura , Kenji Toma , Takeru K. Suzuki , Shu-ichiro Inutsuka

The sidereal anisotropy of galactic cosmic ray (GCR) intensity observed with the Tibet Air Shower (AS) experiment still awaits theoretical interpretation. The observed global feature of the anisotropy is well reproduced by a superposition…

Earth and Planetary Astrophysics · Physics 2009-09-08 Y. Mizoguchi , K. Munakata , M. Takita , J. Kota

In the interstellar medium of galaxies and the intracluster gas of galaxy clusters, the charged particles making up cosmic rays are moving almost exclusively along (but not across) magnetic field lines. The resulting anisotropic transport…

Astrophysics of Galaxies · Physics 2016-08-31 Ruediger Pakmor , Christoph Pfrommer , Christine M. Simpson , Rahul Kannan , Volker Springel

In this second paper in a series dedicated to characterizing shear layers via 2D hybrid (kinetic ions -- fluid electrons) simulations, we study the dynamical role of nonthermal particles (cosmic rays, CRs), either spontaneously generated or…

High Energy Astrophysical Phenomena · Physics 2026-04-15 Naixin Liang , Damiano Caprioli

Cosmic ray (CR) feedback plays a vital role in shaping the formation and evolution of galaxies through their interaction with magnetohydrodynamic waves. In the CR self-confinement scenario, the waves are generated by the CR gyro-resonant…

High Energy Astrophysical Phenomena · Physics 2025-07-23 Xiaochen Sun , Xue-Ning Bai , Xihui Zhao

We investigate the diffusion of cosmic rays (CR) close to their sources. Propagating individual CRs in purely isotropic turbulent magnetic fields with maximal scale of spatial variations Lmax, we find that CRs diffuse anisotropically at…

High Energy Astrophysical Phenomena · Physics 2012-06-29 G. Giacinti , M. Kachelriess , D. V. Semikoz

After more than a century of discovering cosmic rays, a comprehensive description of their origin, propagation, and composition still eludes us. One of the difficulties is that these particles interact with magnetic fields; therefore, their…

High Energy Astrophysical Phenomena · Physics 2023-07-13 Vanessa López-Barquero , Paolo Desiati